crates/rust-analyzer/src/main_loop.rs

   1 //! The main loop of `rust-analyzer` responsible for dispatching LSP
   2 //! requests/replies and notifications back to the client.
   3 use std::{
   4     borrow::Cow,
   5     env, fmt, panic,
   6     time::{Duration, Instant},
   7 };
   8
   9 use crossbeam_channel::{select, Receiver};
  10 use lsp_server::{Connection, Notification, Request, Response};
  11 use lsp_types::{notification::Notification as _, DidChangeTextDocumentParams};
  12 use ra_db::VfsPath;
  13 use ra_ide::{Canceled, FileId};
  14 use ra_prof::profile;
  15
  16 use crate::{
  17     config::Config,
  18     dispatch::{NotificationDispatcher, RequestDispatcher},
  19     document::DocumentData,
  20     from_proto,
  21     global_state::{file_id_to_url, url_to_file_id, GlobalState, Status},
  22     handlers, lsp_ext,
  23     lsp_utils::{apply_document_changes, is_canceled, notification_is, Progress},
  24     Result,
  25 };
  26 use ra_project_model::ProjectWorkspace;
  27 use vfs::ChangeKind;
  28
  29 pub fn main_loop(config: Config, connection: Connection) -> Result<()> {
  30     log::info!("initial config: {:#?}", config);
  31
  32     // Windows scheduler implements priority boosts: if thread waits for an
  33     // event (like a condvar), and event fires, priority of the thread is
  34     // temporary bumped. This optimization backfires in our case: each time the
  35     // `main_loop` schedules a task to run on a threadpool, the worker threads
  36     // gets a higher priority, and (on a machine with fewer cores) displaces the
  37     // main loop! We work-around this by marking the main loop as a
  38     // higher-priority thread.
  39     //
  40     // https://docs.microsoft.com/en-us/windows/win32/procthread/scheduling-priorities
  41     // https://docs.microsoft.com/en-us/windows/win32/procthread/priority-boosts
  42     // https://github.com/rust-analyzer/rust-analyzer/issues/2835
  43     #[cfg(windows)]
  44     unsafe {
  45         use winapi::um::processthreadsapi::*;
  46         let thread = GetCurrentThread();
  47         let thread_priority_above_normal = 1;
  48         SetThreadPriority(thread, thread_priority_above_normal);
  49     }
  50
  51     GlobalState::new(connection.sender.clone(), config).run(connection.receiver)
  52 }
  53
  54 enum Event {
  55     Lsp(lsp_server::Message),
  56     Task(Task),
  57     Vfs(vfs::loader::Message),
  58     Flycheck(flycheck::Message),
  59 }
  60
  61 #[derive(Debug)]
  62 pub(crate) enum Task {
  63     Response(Response),
  64     Diagnostics(Vec<(FileId, Vec<lsp_types::Diagnostic>)>),
  65     Workspaces(Vec<anyhow::Result<ProjectWorkspace>>),
  66     Unit,
  67 }
  68
  69 impl fmt::Debug for Event {
  70     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
  71         let debug_verbose_not = |not: &Notification, f: &mut fmt::Formatter| {
  72             f.debug_struct("Notification").field("method", &not.method).finish()
  73         };
  74
  75         match self {
  76             Event::Lsp(lsp_server::Message::Notification(not)) => {
  77                 if notification_is::<lsp_types::notification::DidOpenTextDocument>(not)
  78                     || notification_is::<lsp_types::notification::DidChangeTextDocument>(not)
  79                 {
  80                     return debug_verbose_not(not, f);
  81                 }
  82             }
  83             Event::Task(Task::Response(resp)) => {
  84                 return f
  85                     .debug_struct("Response")
  86                     .field("id", &resp.id)
  87                     .field("error", &resp.error)
  88                     .finish();
  89             }
  90             _ => (),
  91         }
  92         match self {
  93             Event::Lsp(it) => fmt::Debug::fmt(it, f),
  94             Event::Task(it) => fmt::Debug::fmt(it, f),
  95             Event::Vfs(it) => fmt::Debug::fmt(it, f),
  96             Event::Flycheck(it) => fmt::Debug::fmt(it, f),
  97         }
  98     }
  99 }
 100
 101 impl GlobalState {
 102     fn run(mut self, inbox: Receiver<lsp_server::Message>) -> Result<()> {
 103         if self.config.linked_projects.is_empty() && self.config.notifications.cargo_toml_not_found
 104         {
 105             self.show_message(
 106                 lsp_types::MessageType::Error,
 107                 "rust-analyzer failed to discover workspace".to_string(),
 108             );
 109         };
 110
 111         let save_registration_options = lsp_types::TextDocumentSaveRegistrationOptions {
 112             include_text: Some(false),
 113             text_document_registration_options: lsp_types::TextDocumentRegistrationOptions {
 114                 document_selector: Some(vec![
 115                     lsp_types::DocumentFilter {
 116                         language: None,
 117                         scheme: None,
 118                         pattern: Some("**/*.rs".into()),
 119                     },
 120                     lsp_types::DocumentFilter {
 121                         language: None,
 122                         scheme: None,
 123                         pattern: Some("**/Cargo.toml".into()),
 124                     },
 125                     lsp_types::DocumentFilter {
 126                         language: None,
 127                         scheme: None,
 128                         pattern: Some("**/Cargo.lock".into()),
 129                     },
 130                 ]),
 131             },
 132         };
 133
 134         let registration = lsp_types::Registration {
 135             id: "textDocument/didSave".to_string(),
 136             method: "textDocument/didSave".to_string(),
 137             register_options: Some(serde_json::to_value(save_registration_options).unwrap()),
 138         };
 139         self.send_request::<lsp_types::request::RegisterCapability>(
 140             lsp_types::RegistrationParams { registrations: vec![registration] },
 141             |_, _| (),
 142         );
 143
 144         self.fetch_workspaces();
 145
 146         while let Some(event) = self.next_event(&inbox) {
 147             if let Event::Lsp(lsp_server::Message::Notification(not)) = &event {
 148                 if not.method == lsp_types::notification::Exit::METHOD {
 149                     return Ok(());
 150                 }
 151             }
 152             self.handle_event(event)?
 153         }
 154
 155         Err("client exited without proper shutdown sequence")?
 156     }
 157
 158     fn next_event(&self, inbox: &Receiver<lsp_server::Message>) -> Option<Event> {
 159         select! {
 160             recv(inbox) -> msg =>
 161                 msg.ok().map(Event::Lsp),
 162
 163             recv(self.task_pool.receiver) -> task =>
 164                 Some(Event::Task(task.unwrap())),
 165
 166             recv(self.loader.receiver) -> task =>
 167                 Some(Event::Vfs(task.unwrap())),
 168
 169             recv(self.flycheck_receiver) -> task =>
 170                 Some(Event::Flycheck(task.unwrap())),
 171         }
 172     }
 173
 174     fn handle_event(&mut self, event: Event) -> Result<()> {
 175         let loop_start = Instant::now();
 176         // NOTE: don't count blocking select! call as a loop-turn time
 177         let _p = profile("GlobalState::handle_event");
 178
 179         log::info!("handle_event({:?})", event);
 180         let queue_count = self.task_pool.handle.len();
 181         if queue_count > 0 {
 182             log::info!("queued count = {}", queue_count);
 183         }
 184
 185         let prev_status = self.status;
 186         match event {
 187             Event::Lsp(msg) => match msg {
 188                 lsp_server::Message::Request(req) => self.on_request(loop_start, req)?,
 189                 lsp_server::Message::Notification(not) => {
 190                     self.on_notification(not)?;
 191                 }
 192                 lsp_server::Message::Response(resp) => self.complete_request(resp),
 193             },
 194             Event::Task(task) => {
 195                 match task {
 196                     Task::Response(response) => self.respond(response),
 197                     Task::Diagnostics(diagnostics_per_file) => {
 198                         for (file_id, diagnostics) in diagnostics_per_file {
 199                             self.diagnostics.set_native_diagnostics(file_id, diagnostics)
 200                         }
 201                     }
 202                     Task::Workspaces(workspaces) => self.switch_workspaces(workspaces),
 203                     Task::Unit => (),
 204                 }
 205                 self.analysis_host.maybe_collect_garbage();
 206             }
 207             Event::Vfs(mut task) => {
 208                 let _p = profile("GlobalState::handle_event/vfs");
 209                 loop {
 210                     match task {
 211                         vfs::loader::Message::Loaded { files } => {
 212                             let vfs = &mut self.vfs.write().0;
 213                             for (path, contents) in files {
 214                                 let path = VfsPath::from(path);
 215                                 if !self.mem_docs.contains_key(&path) {
 216                                     vfs.set_file_contents(path, contents)
 217                                 }
 218                             }
 219                         }
 220                         vfs::loader::Message::Progress { n_total, n_done } => {
 221                             if n_total == 0 {
 222                                 self.transition(Status::Invalid);
 223                             } else {
 224                                 let state = if n_done == 0 {
 225                                     self.transition(Status::Loading);
 226                                     Progress::Begin
 227                                 } else if n_done < n_total {
 228                                     Progress::Report
 229                                 } else {
 230                                     assert_eq!(n_done, n_total);
 231                                     self.transition(Status::Ready);
 232                                     Progress::End
 233                                 };
 234                                 self.report_progress(
 235                                     "roots scanned",
 236                                     state,
 237                                     Some(format!("{}/{}", n_done, n_total)),
 238                                     Some(Progress::percentage(n_done, n_total)),
 239                                 )
 240                             }
 241                         }
 242                     }
 243                     // Coalesce many VFS event into a single loop turn
 244                     task = match self.loader.receiver.try_recv() {
 245                         Ok(task) => task,
 246                         Err(_) => break,
 247                     }
 248                 }
 249             }
 250             Event::Flycheck(task) => match task {
 251                 flycheck::Message::AddDiagnostic { workspace_root, diagnostic } => {
 252                     let diagnostics = crate::diagnostics::to_proto::map_rust_diagnostic_to_lsp(
 253                         &self.config.diagnostics,
 254                         &diagnostic,
 255                         &workspace_root,
 256                     );
 257                     for diag in diagnostics {
 258                         match url_to_file_id(&self.vfs.read().0, &diag.url) {
 259                             Ok(file_id) => self.diagnostics.add_check_diagnostic(
 260                                 file_id,
 261                                 diag.diagnostic,
 262                                 diag.fixes,
 263                             ),
 264                             Err(err) => {
 265                                 log::error!("File with cargo diagnostic not found in VFS: {}", err);
 266                             }
 267                         };
 268                     }
 269                 }
 270
 271                 flycheck::Message::Progress(status) => {
 272                     let (state, message) = match status {
 273                         flycheck::Progress::DidStart => {
 274                             self.diagnostics.clear_check();
 275                             (Progress::Begin, None)
 276                         }
 277                         flycheck::Progress::DidCheckCrate(target) => {
 278                             (Progress::Report, Some(target))
 279                         }
 280                         flycheck::Progress::DidCancel => (Progress::End, None),
 281                         flycheck::Progress::DidFinish(result) => {
 282                             if let Err(err) = result {
 283                                 log::error!("cargo check failed: {}", err)
 284                             }
 285                             (Progress::End, None)
 286                         }
 287                     };
 288
 289                     self.report_progress("cargo check", state, message, None);
 290                 }
 291             },
 292         }
 293
 294         let state_changed = self.process_changes();
 295         if prev_status == Status::Loading && self.status == Status::Ready {
 296             if let Some(flycheck) = &self.flycheck {
 297                 flycheck.update();
 298             }
 299         }
 300
 301         if self.status == Status::Ready && (state_changed || prev_status == Status::Loading) {
 302             let subscriptions = self
 303                 .mem_docs
 304                 .keys()
 305                 .map(|path| self.vfs.read().0.file_id(&path).unwrap())
 306                 .collect::<Vec<_>>();
 307
 308             self.update_file_notifications_on_threadpool(subscriptions);
 309         }
 310
 311         if let Some(diagnostic_changes) = self.diagnostics.take_changes() {
 312             for file_id in diagnostic_changes {
 313                 let url = file_id_to_url(&self.vfs.read().0, file_id);
 314                 let diagnostics = self.diagnostics.diagnostics_for(file_id).cloned().collect();
 315                 let version = from_proto::vfs_path(&url)
 316                     .map(|path| self.mem_docs.get(&path)?.version)
 317                     .unwrap_or_default();
 318
 319                 self.send_notification::<lsp_types::notification::PublishDiagnostics>(
 320                     lsp_types::PublishDiagnosticsParams { uri: url, diagnostics, version },
 321                 );
 322             }
 323         }
 324
 325         let loop_duration = loop_start.elapsed();
 326         if loop_duration > Duration::from_millis(100) {
 327             log::warn!("overly long loop turn: {:?}", loop_duration);
 328             if env::var("RA_PROFILE").is_ok() {
 329                 self.show_message(
 330                     lsp_types::MessageType::Error,
 331                     format!("overly long loop turn: {:?}", loop_duration),
 332                 )
 333             }
 334         }
 335         Ok(())
 336     }
 337
 338     fn on_request(&mut self, request_received: Instant, req: Request) -> Result<()> {
 339         self.register_request(&req, request_received);
 340
 341         RequestDispatcher { req: Some(req), global_state: self }
 342             .on_sync::<lsp_ext::ReloadWorkspace>(|s, ()| Ok(s.fetch_workspaces()))?
 343             .on_sync::<lsp_ext::JoinLines>(|s, p| handlers::handle_join_lines(s.snapshot(), p))?
 344             .on_sync::<lsp_ext::OnEnter>(|s, p| handlers::handle_on_enter(s.snapshot(), p))?
 345             .on_sync::<lsp_types::request::Shutdown>(|_, ()| Ok(()))?
 346             .on_sync::<lsp_types::request::SelectionRangeRequest>(|s, p| {
 347                 handlers::handle_selection_range(s.snapshot(), p)
 348             })?
 349             .on_sync::<lsp_ext::MatchingBrace>(|s, p| {
 350                 handlers::handle_matching_brace(s.snapshot(), p)
 351             })?
 352             .on_sync::<lsp_ext::MemoryUsage>(|s, p| handlers::handle_memory_usage(s, p))?
 353             .on::<lsp_ext::AnalyzerStatus>(handlers::handle_analyzer_status)?
 354             .on::<lsp_ext::SyntaxTree>(handlers::handle_syntax_tree)?
 355             .on::<lsp_ext::ExpandMacro>(handlers::handle_expand_macro)?
 356             .on::<lsp_ext::ParentModule>(handlers::handle_parent_module)?
 357             .on::<lsp_ext::Runnables>(handlers::handle_runnables)?
 358             .on::<lsp_ext::InlayHints>(handlers::handle_inlay_hints)?
 359             .on::<lsp_ext::CodeActionRequest>(handlers::handle_code_action)?
 360             .on::<lsp_ext::ResolveCodeActionRequest>(handlers::handle_resolve_code_action)?
 361             .on::<lsp_ext::HoverRequest>(handlers::handle_hover)?
 362             .on::<lsp_types::request::OnTypeFormatting>(handlers::handle_on_type_formatting)?
 363             .on::<lsp_types::request::DocumentSymbolRequest>(handlers::handle_document_symbol)?
 364             .on::<lsp_types::request::WorkspaceSymbol>(handlers::handle_workspace_symbol)?
 365             .on::<lsp_types::request::GotoDefinition>(handlers::handle_goto_definition)?
 366             .on::<lsp_types::request::GotoImplementation>(handlers::handle_goto_implementation)?
 367             .on::<lsp_types::request::GotoTypeDefinition>(handlers::handle_goto_type_definition)?
 368             .on::<lsp_types::request::Completion>(handlers::handle_completion)?
 369             .on::<lsp_types::request::CodeLensRequest>(handlers::handle_code_lens)?
 370             .on::<lsp_types::request::CodeLensResolve>(handlers::handle_code_lens_resolve)?
 371             .on::<lsp_types::request::FoldingRangeRequest>(handlers::handle_folding_range)?
 372             .on::<lsp_types::request::SignatureHelpRequest>(handlers::handle_signature_help)?
 373             .on::<lsp_types::request::PrepareRenameRequest>(handlers::handle_prepare_rename)?
 374             .on::<lsp_types::request::Rename>(handlers::handle_rename)?
 375             .on::<lsp_types::request::References>(handlers::handle_references)?
 376             .on::<lsp_types::request::Formatting>(handlers::handle_formatting)?
 377             .on::<lsp_types::request::DocumentHighlightRequest>(
 378                 handlers::handle_document_highlight,
 379             )?
 380             .on::<lsp_types::request::CallHierarchyPrepare>(
 381                 handlers::handle_call_hierarchy_prepare,
 382             )?
 383             .on::<lsp_types::request::CallHierarchyIncomingCalls>(
 384                 handlers::handle_call_hierarchy_incoming,
 385             )?
 386             .on::<lsp_types::request::CallHierarchyOutgoingCalls>(
 387                 handlers::handle_call_hierarchy_outgoing,
 388             )?
 389             .on::<lsp_types::request::SemanticTokensRequest>(handlers::handle_semantic_tokens)?
 390             .on::<lsp_types::request::SemanticTokensEditsRequest>(
 391                 handlers::handle_semantic_tokens_edits,
 392             )?
 393             .on::<lsp_types::request::SemanticTokensRangeRequest>(
 394                 handlers::handle_semantic_tokens_range,
 395             )?
 396             .on::<lsp_ext::Ssr>(handlers::handle_ssr)?
 397             .finish();
 398         Ok(())
 399     }
 400     fn on_notification(&mut self, not: Notification) -> Result<()> {
 401         NotificationDispatcher { not: Some(not), global_state: self }
 402             .on::<lsp_types::notification::Cancel>(|this, params| {
 403                 let id: lsp_server::RequestId = match params.id {
 404                     lsp_types::NumberOrString::Number(id) => id.into(),
 405                     lsp_types::NumberOrString::String(id) => id.into(),
 406                 };
 407                 this.cancel(id);
 408                 Ok(())
 409             })?
 410             .on::<lsp_types::notification::DidOpenTextDocument>(|this, params| {
 411                 if let Ok(path) = from_proto::vfs_path(&params.text_document.uri) {
 412                     if this
 413                         .mem_docs
 414                         .insert(path.clone(), DocumentData::new(params.text_document.version))
 415                         .is_some()
 416                     {
 417                         log::error!("duplicate DidOpenTextDocument: {}", path)
 418                     }
 419                     this.vfs
 420                         .write()
 421                         .0
 422                         .set_file_contents(path, Some(params.text_document.text.into_bytes()));
 423                 }
 424                 Ok(())
 425             })?
 426             .on::<lsp_types::notification::DidChangeTextDocument>(|this, params| {
 427                 if let Ok(path) = from_proto::vfs_path(&params.text_document.uri) {
 428                     let DidChangeTextDocumentParams { text_document, content_changes } = params;
 429                     let vfs = &mut this.vfs.write().0;
 430                     let world = this.snapshot();
 431                     let file_id = vfs.file_id(&path).unwrap();
 432
 433                     // let file_id = vfs.file_id(&path).unwrap();
 434                     let mut text = String::from_utf8(vfs.file_contents(file_id).to_vec()).unwrap();
 435                     let line_index = world.analysis.file_line_index(file_id)?;
 436                     apply_document_changes(&mut text, content_changes, Cow::Borrowed(&line_index));
 437
 438                     // The version passed in DidChangeTextDocument is the version after all edits are applied
 439                     // so we should apply it before the vfs is notified.
 440                     let doc = this.mem_docs.get_mut(&path).unwrap();
 441                     doc.version = text_document.version;
 442
 443                     vfs.set_file_contents(path.clone(), Some(text.into_bytes()));
 444                 }
 445                 Ok(())
 446             })?
 447             .on::<lsp_types::notification::DidCloseTextDocument>(|this, params| {
 448                 let mut version = None;
 449                 if let Ok(path) = from_proto::vfs_path(&params.text_document.uri) {
 450                     match this.mem_docs.remove(&path) {
 451                         Some(doc) => version = doc.version,
 452                         None => log::error!("orphan DidCloseTextDocument: {}", path),
 453                     }
 454
 455                     this.semantic_tokens_cache.lock().unwrap().remove(&params.text_document.uri);
 456
 457                     if let Some(path) = path.as_path() {
 458                         this.loader.handle.invalidate(path.to_path_buf());
 459                     }
 460                 }
 461
 462                 // Clear the diagnostics for the previously known version of the file.
 463                 // This prevents stale "cargo check" diagnostics if the file is
 464                 // closed, "cargo check" is run and then the file is reopened.
 465                 this.send_notification::<lsp_types::notification::PublishDiagnostics>(
 466                     lsp_types::PublishDiagnosticsParams {
 467                         uri: params.text_document.uri,
 468                         diagnostics: Vec::new(),
 469                         version,
 470                     },
 471                 );
 472                 Ok(())
 473             })?
 474             .on::<lsp_types::notification::DidSaveTextDocument>(|this, params| {
 475                 if let Some(flycheck) = &this.flycheck {
 476                     flycheck.update();
 477                 }
 478                 if let Ok(abs_path) = from_proto::abs_path(&params.text_document.uri) {
 479                     this.maybe_refresh(&[(abs_path, ChangeKind::Modify)]);
 480                 }
 481                 Ok(())
 482             })?
 483             .on::<lsp_types::notification::DidChangeConfiguration>(|this, _params| {
 484                 // As stated in https://github.com/microsoft/language-server-protocol/issues/676,
 485                 // this notification's parameters should be ignored and the actual config queried separately.
 486                 this.send_request::<lsp_types::request::WorkspaceConfiguration>(
 487                     lsp_types::ConfigurationParams {
 488                         items: vec![lsp_types::ConfigurationItem {
 489                             scope_uri: None,
 490                             section: Some("rust-analyzer".to_string()),
 491                         }],
 492                     },
 493                     |this, resp| {
 494                         log::debug!("config update response: '{:?}", resp);
 495                         let Response { error, result, .. } = resp;
 496
 497                         match (error, result) {
 498                             (Some(err), _) => {
 499                                 log::error!("failed to fetch the server settings: {:?}", err)
 500                             }
 501                             (None, Some(mut configs)) => {
 502                                 if let Some(json) = configs.get_mut(0) {
 503                                     // Note that json can be null according to the spec if the client can't
 504                                     // provide a configuration. This is handled in Config::update below.
 505                                     let mut config = this.config.clone();
 506                                     config.update(json.take());
 507                                     this.update_configuration(config);
 508                                 }
 509                             }
 510                             (None, None) => log::error!(
 511                                 "received empty server settings response from the client"
 512                             ),
 513                         }
 514                     },
 515                 );
 516
 517                 return Ok(());
 518             })?
 519             .on::<lsp_types::notification::DidChangeWatchedFiles>(|this, params| {
 520                 for change in params.changes {
 521                     if let Ok(path) = from_proto::abs_path(&change.uri) {
 522                         this.loader.handle.invalidate(path);
 523                     }
 524                 }
 525                 Ok(())
 526             })?
 527             .finish();
 528         Ok(())
 529     }
 530     fn update_file_notifications_on_threadpool(&mut self, subscriptions: Vec<FileId>) {
 531         log::trace!("updating notifications for {:?}", subscriptions);
 532         if self.config.publish_diagnostics {
 533             let snapshot = self.snapshot();
 534             let subscriptions = subscriptions.clone();
 535             self.task_pool.handle.spawn(move || {
 536                 let diagnostics = subscriptions
 537                     .into_iter()
 538                     .filter_map(|file_id| {
 539                         handlers::publish_diagnostics(&snapshot, file_id)
 540                             .map_err(|err| {
 541                                 if !is_canceled(&*err) {
 542                                     log::error!("failed to compute diagnostics: {:?}", err);
 543                                 }
 544                                 ()
 545                             })
 546                             .ok()
 547                             .map(|diags| (file_id, diags))
 548                     })
 549                     .collect::<Vec<_>>();
 550                 Task::Diagnostics(diagnostics)
 551             })
 552         }
 553         self.task_pool.handle.spawn({
 554             let subs = subscriptions;
 555             let snap = self.snapshot();
 556             move || {
 557                 snap.analysis.prime_caches(subs).unwrap_or_else(|_: Canceled| ());
 558                 Task::Unit
 559             }
 560         });
 561     }
 562 }